JP2963278B2 - Network element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network element such as a chip-type network resistor.

[0002]

2. Description of the Related Art A network element has a plurality of electrodes because a plurality of circuit elements are formed on one substrate.
In this type of network element, a concave portion is provided on the side surface of the chip substrate in order to separate between the electrodes, and conventionally, each electrode is formed in a convex portion between the concave portions, or an electrode is formed in the concave portion. doing. FIG. 6 shows a chip substrate 61.
An example is shown in which an electrode 63 is formed in a concave portion 62 provided on the side surface of FIG. Although only the upper surface of the electrode 63 is shown here, the electrode 63 is
Are formed on the concave wall of the side surface of the chip substrate 61, and the electrode 63 is integrally formed of the upper surface, the lower surface and the side surface. Although not shown, each electrode 63 is appropriately connected to a circuit element in the chip substrate 61.

[0003]

In the above-described network element in which an electrode is formed in a concave portion, the smaller the element is, the shorter the distance between adjacent electrodes becomes. As shown in FIG. 7A and 7B, there is a possibility that the adjacent upper surface portions 63a of the electrodes 63 may be short-circuited due to the leakage due to the flux residue 64 on the upper surface portions 63a of the electrodes 63, and as shown in FIG. 7C, when the lower surface portion 63b of the electrode 63 is soldered to the land electrode 68 of the circuit board 67 due to excessive solder 66, as shown in FIG. There is a risk of short circuit.

The present invention has been made in view of the above problems, and has as its object to provide a network element in which a short circuit does not easily occur between adjacent electrodes.

[0005]

The network element according to the present invention is provided with a plurality of electrodes formed from the side surface of the chip substrate to the upper surface and / or the lower surface, and each electrode is formed in a concave portion of the chip substrate. In what was done,
A notch recess is formed between adjacent electrodes on the upper surface and / or lower surface of the chip substrate.

In this network element, even if flux residue is generated near the electrode on the upper surface, or even if the solder is excessive, they enter into the notch recess between the electrodes, and a short circuit is avoided by the step. In addition, when a notch recess is provided between the electrodes on the lower surface, excess solder spillage escapes to this portion, which also makes it difficult to cause a short circuit between the electrodes.

[0007]

The present invention will be described in more detail with reference to the following examples. FIG. 1 is a perspective view of a chip type network resistor showing one embodiment of the present invention. This chip type network resistor 10 has eight concave semi-circular recesses 3 in plan view on the long side surface 2 of the flat ceramic substrate 1. An electrode 4 is formed in each of the recesses 3. Each of the electrodes 4 is integrally formed of an upper electrode portion 4a formed on the upper surface of the ceramic substrate 1, a lower electrode portion 4b formed on the lower surface, and a side electrode portion 4c formed on the side surface of the concave portion 3. I have. Although a resistive film is appropriately formed between the electrodes on the ceramic substrate 1, it is not shown here because it is not a main part of the present invention.

The most characteristic feature of the network resistor 10 is that a notch 5 is provided between the adjacent electrodes 4 and extends from the top edge to the side face of the ceramic substrate 1. Ceramic substrate 1 between 4
Is provided with a notched concave portion 6 extending from the lower surface edge to the side surface. When flow soldering is performed on the network resistor 10, even if a flux residue is generated in the vicinity of the upper surface electrode portion 4 a, as shown in FIG.
Flux residue 7 accumulates at the bottom of the substrate, but due to the step between the notch recess 5 and the upper surface electrode 4a, the degree of conduction between the adjacent upper surface electrode portions 4a due to the flux residue 7 is reduced. Similarly, at the time of flow soldering, the upper surface electrode portion 4a
Even if excess solder occurs, as shown in FIG.
The excess solder 8 flows into the side wall of the notch 5, but the distance between adjacent electrodes is longer than when there is no notch 5, and the excess solder 8 between the adjacent upper electrode 4 a causes a short circuit. Never.

In this network resistor 10, even if excessive solder occurs between the lower electrode portion and the land electrode of the circuit board during reflow soldering, as shown in FIG. Soldering part 13 between electrode part 4b and land electrode 12 of circuit board 11
Thus, even if there is some excess solder, the raised portion of the solder escapes into the notch recess 6, so that the adjacent lower surface electrode portion 4b does not short-circuit due to excessive solder.

FIG. 2 is a perspective view showing a chip type network resistor according to another embodiment of the present invention. The feature of the network resistor 20 of this embodiment is that the network resistor of FIG. 1 has cutout recesses 5 and 6 on both the upper surface and the lower surface of the ceramic substrate 1, whereas the network resistor of FIG. That is, a notch concave portion 5 extending from the upper edge to the side surface of the ceramic substrate 1 between the electrodes 4 is provided. As shown in FIGS. 4 (a) and 4 (b), the provision of the notch recesses 5 causes leakage between the adjacent electrodes due to flux residue during flow soldering and short-circuit between the adjacent electrodes due to excessive soldering. Occurrence is reduced.

FIG. 3 is a perspective view showing a chip type network resistor according to still another embodiment of the present invention. The feature of the network resistor 30 of this embodiment is that the network resistor of FIG. 1 has cutout recesses 5 and 6 on both the upper surface and the lower surface of the ceramic substrate 1, whereas only the lower surface, that is, That is, a notched concave portion 6 extending from the lower edge to the side surface of the ceramic substrate 1 between the electrodes 4 is provided. By providing the notch recess 6, as shown in FIG. 5, excess solder at the time of reflow soldering is released to the notch recess 6, so that a short circuit between adjacent electrodes due to excess solder can be prevented.

Although the network resistor in the above embodiment has been described as an example, the present invention is not limited to this, and can be applied to other network elements.

[0013]

According to the present invention, the notch recess is provided between the adjacent electrodes on the upper surface and / or the lower surface of the chip substrate, so that leakage between the two electrodes due to flux residue of the upper electrode portion during flow soldering and excessive soldering And the occurrence of short circuit due to excessive solder between lower electrodes during reflow soldering can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a chip type network resistor showing one embodiment of the present invention.

FIG. 2 is a perspective view of a chip type network resistor showing another embodiment of the present invention.

FIG. 3 is a perspective view of a chip-type network resistor showing still another embodiment of the present invention.

FIG. 4 is a partial cross-sectional view for explaining the influence of a flux residue and excess solder during flow soldering of the chip-type network resistor shown in FIGS. 1 and 2;

FIG. 5 is a partial cross-sectional view for explaining the influence of excessive soldering during reflow soldering of the chip type network resistor shown in FIGS. 1 and 3;

FIG. 6 is a plan view showing a conventional chip-type network resistor.

FIG. 7 is a partial cross-sectional view for explaining the influence of a flux residue and excess solder during flow soldering and reflow soldering of the conventional chip-type network resistor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ceramic substrate 4 Electrode 5, 6 Notch recess

Claims (1)

(57) [Claims] 1. A network element in which a plurality of electrodes are provided extending from the side surface of a chip substrate to the upper surface and / or lower surface, and each electrode is formed in a concave portion of the chip substrate. Wherein a notch recess is formed between adjacent electrodes.